Skin conditions are usually temporary and can be caused by environmental factors, medications, lifestyle, etc. The most common skin condition is dehydrated skin or skin that's lacking water.
Dehydrated skin is not dry skin. It can look and feel like dry skin (flaky patches anyone), but unlike dry skin, you may still be able to produce sebum and oil. True dry skin lacks oil. I have dehydrated skin, but not dry skin – I produce a bit oily in my t-zone, but the rest of my skin is soft and feels "normal." Dehydrated skin also has a myriad of contradicting symptoms. When my skin is dehydrated, I'll get more oily, and I might flake on my nose (which is already oily) and chin. When I use a sheet mask, it's always these "oily" spots (my forehead mostly, but also my nose), that absorb and dry out the mask the quickest.
Medications: especially topical acne products containing benzoyl peroxide, tretinoin, or salicylic acid.
Alcohol: both ingesting it, as well as applying products contain alcohol
Damaged skin barrier: A healthy skin barrier helps to keep water in, a damaged one can let the water evaporate faster while letting irritating substances in.
Dry environment: this includes general climate, as well as indoor heating and air conditioning.
Dull or sallow skin
Shiny looking, but not necessarily oily (although it could be)
Fine wrinkles when pulled taught – skin should be bouncy!
Feels dry and tight – this can be after cleansing, or even a little while after you've applied moisturizers!
Oily in some places, dry in some places, and flakiness in any of these places. You know you have dehydrated skin when you're flaking over top of those oily places.
So, what does a skincare routine to treat dehydrated skin look like? Well, it looks like that insane multilayered skin care routine that can consist of ten plus steps. If you want something a bit more simple, the quick and easy, back to basics routine consists of three very easy steps – cleanse, hydrate, and seal.
Cleanse: Use a gentle cleanser, preferably ph balanced (look for something no higher than 5.5). Cleansers with a high ph, sulfates and surfactants will only dehydrate your skin more.
Hydrate: Now, you don't need to use twenty different serums to do this. Try a hydrating toner like the Hada Labo Gokujyun lotion, or just a basic hyaluronic acid serum. For something a little more time consuming, try a sheet mask (but look for one without alcohol).
Seal: The last step is to seal everything in with an occlusive cream. This can be a lightweight lotion or emulsion, or even a heavier cream, If you're regularly more oily, I'd suggest a lightweight lotion, if you're dryer, go with a cream, or even a facial oil. Gel based creams are great, but if you still feel like your skin is tight after a gel, you may want to switch to a heavier, more emollient moisturizer.